Low back pain is a major cause of morbidity, disability, limitation of activity, and economic loss. Most studies have found that 60-80% of people are affected with low back pain at some time during their lives (Hult 1954, Biering-Sorensen 1982, Svensson and Andersson 1982, Frymoyer et al 1983). Some sports have been related to low back and even to sciatica. In particular, sports which involve twisting, such as golf, bowling, and tennis, have been associated with lumbar disc herniations (Iselsey 1975). Other studies have suggested a relationship between mild non-disabling back pain and jogging and cross country skiing. A special example is the relationship between isthmic spondylolisthesis and gymnastics or American football. Regarding spinal posture, in two studies in which the extent of forward flexibility was measured before the occurrence of low back pain (Dieck 1982, Biering-Sorenson 1984), restricted forward flexion was associated with a decreased risk of subsequent low back pain. This result suggests that restricted forward flexion may be indicative of a more stable lumbar spine that is less susceptible to injury (White & Panjabi 1978). It is widely believed in ergonomics that a neutral posture is safer.
Motion sensors for kinetic activities such as golf, tennis and the like have long been known. The use of available feedback to indicate level of accomplishment to the user via pitch, duration or the modulation of either, is frequently used. Feedback with regard to spinal muscle can be considered a case of learning to relax a specific group of muscles with the aid of electronically delivered information. There have been two separate approaches to feedback in the field of back pain: a general relaxation technique and EMG feedback as part of a wider treatment package.
It is an object of the present system to overcome the disadvantages and problems in the prior art. This object is primarily accomplished by monitoring regions of a user's spine during work and physical activities, and providing biofeedback to the user.